Transformer.



G. LB G. FORTESGUE. TRANSFORMER.

APPLICATION FILED JUNE 8, 1907.

PATENTED FEB. 18, 1908,

7l l@ @n l Vl. l-

UNITED STATES PATENT QFFICE.

CHARLES LE G. FORTESCUE, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC d: MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

TRANSFORMER.

ne. crains.

To @ZZ whom 'it ena-y concern:

Be it known that I, CHARLES Ln G. FOR- Tnsoun, a subject oi the Kimr of Great Britain, `and a resident of l/Vilkinsburg, in the county of Allegheny and State of Pennsyl- Vania, have invented a new and useful Im-r vIn electrical transformers, as now mostY commonly constructed for commercial use, the 'windings are provided with leads that may be comected in a plurality of different arrangements in order to obtain a variety of voltage ratios. However, as the windings and leads have heretofore been arranged with respect to each other, considerable unbalancing of the fluxes traversing corresponding portions 'of the magnetic circuits usuallynoccurs, while a relatively large number of leads has been necessary in order to obtain a large or a desired range of voltages. The

f that areY ordinarily leads haveialso been connected near the terminals ci the transformer, thus weakening the insulation of the portions of the winding subjected to the highest voltage strains.VV

In 'the present transformer, only a compara-tively small number of leads are required for obtaining a large number of voltage steps, and the leads are connected to the windings in such a manner that, when eli'ecting voltage adjustment, correspondingly located portions of the winding are removed from circuit in succession, whereby unbalancing of the magnetic circuits is avoid-ed. The insulation of the transformer also is not weakened by the presence of the leads.

Figure 1, of the accompanying drawings,

is a diagrammatic view of a portion. of a transformer that embodies my invention, and Figs. 2 to 8, inclusive, are views of the terminal block of\ the .transformer which illustrate the connections whereby voltage adjustment may be effected. r Mounted upon a portion 1 of the magnetizable core of the transformer, is a plurality of coils 2 to 19, inclusive, the coils 2, 7, 8, 13, 14, and 19 constituting the low voltage Specication of Letters Patent.y I Application iilerl June 8. 14907. Serial No.3'\78.013.

inductance in the transformer, and venting', as far as possible, unbalancin'g of Patented Feb. 18, 1908.

1)/ winding of the transformer, and coils 3, 4, 5, 6, 9, 10, 11,12,'15,16,17, andlS constituting the high voltage winding. The high voltage winding is divided into three sections, each, comprising a group of four coils, and the said sections are interpolated in a symmetrical arrangement with the four sections into which the/low voltage winding is fdivided.. Each ofi the two inner sections of the low voltage winding comprises two coils and each of the v'outer sections comprises a single coil. The'v grouping of the coils and the symmetricalarrangement of the grou s are provided for the purpose of reducing t "e lea age and for pretheiinagnetic fluxes in corresponding portions/ofthe core. e

The outer extremities of the coils 2 and 19 are connected, respectively, to terminals 20 and 271 upon a terminal board or block 22, and'f'the inner 'extremities are connected,

respectively, to terminals 23 and 24. Suitable intermediate points, that are located nearer the inner extremities ofthe coils 2 and 19 than their outer extremities, are connected respectively to the terminals 25 and 26.

' The outer extremities of the coils 7 and 14 are connected, res ectively, to terminals 27 and 28, and suite. le intermediate points of the said coils are connected to terminals 29 and 30, the distances between the said intermediate points and the outer extremities of the coils l7 and le being greaterthan the distances between the intermediate points in the coils 2 and 19, and their inner entremities. If the portions of the winding included between the terminals 127 and 29 and between terminals 28 and 30 are of twice' the active length ofthe portions oi the Winding that are included between terminals 23 and 25 and between terminals 24 and 26, equal voltage steps may be obtained. throughout the range of adjustment. f

In Fig. 2 areshown the connections upon the terminal blockv whereby the maXirnuIn 'voltage o'f the transfer.l ner may be obtained,

the terminals 23 and 27 being connected together, as are also terminals 24 and 28, in order to include in circuit all oi the low vol-o tage winding. Y

In'Eig. 3, terminals 25 and 27 are connected together, as are also terminals 24 and 28, so that a portionjlof the Winding 2 is excluded from the circuit. The terminals 25 .and 27 with which the other winding is in -r olated to form a symmetrical arrangement, o means i for connecting ditl'erent pairs of points of the said sections to adjust the voltage ratio of the transformer.

2. In a transformer, the combination with primary and secondary windings, each comprising a plurality of sections, 'ie sections of P, V 1 In Fig. 6 portions of the coils i and 14 are I excluded from the circuit, since terminals 23 and 29 are connected together, as are also terminals 34 and 30. Portions of windings j 3, Y, and 14 are excluded trom the circuit in j Fig. 7, since terminals 25 and 29 are connected together, as are also terminals 24 and 30.

prising a plurality of sections, the sections of i In Fie. 8 terminals 25 and 29 are connected together, as are also terminals 26 and 30,

` rical arrangement, of means for connectin a so that ortions of windings 2, T, 14, and 19 are excI uded from the circuit. seen that the leads n hereby voltage adjustment may be effected are connected to the inner portions of the winding where the voltage strains are not excessive and, consequently, the insulation of the transformer is not weakened by the presence of the leads."

Only a comparatively small number of leads to be connected to intermediate points of the coils are necessary in the present arrange; ment iii order'to obtain a relatively large number of steps in the voltage. meti-v ot' the arrangement of coils is not at all disturbed by the connections illustrated T luis itI is in Figs. 2, 4, 6, and S, while. with the con ,nections illustrated in Figs. Il, and 7, the

symmetrical arrangement is only slightly disturbed, so that little or no unbalancing of the magnetic circuits occurs during voltage adjustment. f

It will, of course, be understood that either orboth windings of the transformer may be provided with leads, as desired.

lclaiin as my invention:

1. ln a transformer, the combination with primary and secondary Awiiulings at least one of which comprises a plurality of sections,

the windings being interpolated in a symmetrical arrangement, of means for connecting a plurality of diflerent pairs of points in the sections of one winding between which a section of the other winding is located.

3. In a transformer, the combination with primary and secondary windings each comthe windings beinginterpolated inasymmetplurality of different pairs of points in t e sections of one winding that are symmetrically located with respect to a section of the other winding.

4. In a transformer, the combination with primary and secondary windings, each comprising a plurality of sections, tie sections of the windings being interpolated in a symmetrical arrangement, of means for removing from, the circuit portions of the sections of one winding between which a section of the other winding is located. Y

5. In a transformer, the combination wit-h primary and secondary windings, each cornprising a plurality of sections, t ie sections of the windings being interpolated in a symmetrical arrangement, of means for removing from the circuit portions of the sections of one winding that arc symmetrically located with respect to the other winding.

In testimony whereof, I have hereunto subscribed my naine this 31st day of May,

CIL-XRUCS LE l. FORTESCUE. 'itnesses:

-()rio S. SeiiAiuER,

Biizxisr Ilixis. 

